on heatin, 0.02mol of the element M reacts with 0.025mol of oxygen gas. What is the empirical formula of the oxide of M?

The mole ratio is .025/.02=1.25 or 5/4

So the O2 has a ratio of 5 to one Metal.

M4 (O2)5= M>sub>4O10 or writing it in lowest whole numbers
M2O5

why'd u put the mole ratio as 0.025/0.02 as opposed to 0.02/0.025?

You could have, I did the mole ratio as O2/M, doing it your way would have given M/O2. Same end result.

OOkkk

thnx much